Power tool with light emitting assembly

ABSTRACT

A power tool including an end effector rotatable with respect to the housing, a collar non-rotatably coupled to the housing, an annular printed circuit board (PCB) rotatably fixed with respect to the housing, and a light element operatively connected to the PCB and adjacent to the end effector and in a recess of the collar and located to illuminate a workpiece machined by the power tool.

FIELD

The present application relates generally to handheld power tools. Moreparticularly, the present application relates to handheld power toolshaving a light configured to shine onto a workpiece machined by thepower tool.

BACKGROUND

This section provides background information related to the presentdisclosure which is not necessarily prior art. Power tools are oftenused in a variety of conditions ranging from well-lit indoor work spacesto outside construction sites or other areas that are not alwayswell-lit. Accordingly, it is desirable to provide a method or apparatusthat permits a power tool to have a lighting feature that willilluminate the workpiece being machined or worked on by the power tool.Such a lighting feature will assist a user to be able to adequately viewthe workpiece or work area that is being worked on or machined by thepower tool even in substandard light conditions.

Because power tools may be used in adverse environmental conditions, itis desirable to protect such a lighting feature from the adverseenvironmental conditions.

SUMMARY

This section provides a general summary of the disclosure, and is not acomprehensive disclosure of its full scope or all of its features. Inaccordance with one embodiment of the present teachings, a power tool isprovided. The power tool includes a housing, an end effector rotatablewith respect to the housing, a collar non-rotatable with respect to thehousing, a printed circuit board (PCB) fixed with respect to the housingusing a heat stake process, and a lighting element operatively connectedto the PCB. The lighting element is adjacent to the end effector and ina recess of a transparent housing and located to illuminate a workpiecemachined by the power tool.

In accordance with another embodiment of the present teachings, a powertool is provided. The power tool includes a rotatable end effector, anon-rotatable collar, and a circular printed circuit board (PCB).Surface mount lighting elements are operatively connected to the PCB andare adjacent to the end effector to illuminate a workpiece machined bythe power tool. The collar has a transparent cover supporting the PCBand wires configured to provide power to the PCB for illuminating thelighting elements. The lighting elements are annularly arranged on thePCB about the end effector. A portion of the end effector extendsthrough a hole defined by the transparent cover and PCB. The transparentcover defines a groove and the PCB is coupled in the groove using a heatstaking process.

There has thus been outlined, rather broadly, certain embodiments of theinvention in order that the detailed description thereof herein may bebetter understood, and in order that the present contribution to the artmay be better appreciated. There are, of course, additional embodimentsof the invention that will be described below and which will form thesubject matter of the claims appended hereto.

In this respect, before explaining at least one embodiment of theinvention in detail, it is to be understood that the invention is notlimited in its application to the details of construction and to thearrangements of the components set forth in the following description orillustrated in the drawings. The invention is capable of embodiments inaddition to those described and of being practiced and carried out invarious ways. Also, it is to be understood that the phraseology andterminology employed herein, as well as the abstract, are for thepurpose of description and should not be regarded as limiting.

As such, those skilled in the art will appreciate that the conceptionupon which this disclosure is based may readily be utilized as a basisfor the designing of other structures, methods and systems for carryingout the several purposes of the present invention. It is important,therefore, that the claims be regarded as including such equivalentconstructions insofar as they do not depart from the spirit and scope ofthe present invention.

Further areas of applicability will become apparent from the descriptionprovided herein. The description and specific examples in this summaryare intended for purposes of illustration only and are not intended tolimit the scope of the present disclosure.

DRAWINGS

The drawings described herein are for illustrative purposes only ofselected embodiments and not all possible implementations, and are notintended to limit the scope of the present disclosure.

FIGS. 1 a and 1 b represent side views of two embodiments of power toolsaccording to the present teachings;

FIG. 2 represents a nose-piece subassembly of the power tool shown inFIG. 1;

FIG. 3 represents a cross-sectional view of a holder subassemblyassociated with the nosepiece shown in FIG. 2;

FIG. 4 represents a perspective cross-sectional view of the holdersubassembly shown in FIGS. 2 and 3;

FIG. 5 represents a perspective view of a transparent cover-circuitboard subassembly according to the present teachings;

FIG. 6 represents a perspective cross-sectional view of the transparentcircuit board subassembly shown in FIG. 5;

FIG. 7 represents a front perspective view of the subassembly shown inFIG. 5;

FIG. 8 represents a close-up view of the circuit board/transparenthousing interface of the subassembly shown in FIG. 5;

FIG. 9 represents a rear perspective view of an alternate holdersubassembly according to the present teachings;

FIG. 10 represents a perspective cross-sectional view of the holdersubassembly shown in FIG. 9; and

FIG. 11 represents a front view of the holder subassembly shown in FIGS.9 and 10.

Corresponding reference numerals indicate corresponding parts throughoutthe several views of the drawings.

DETAILED DESCRIPTION

Example embodiments will now be described more fully with reference tothe accompanying drawings. According to some embodiments of theinvention, light emitting elements, such as light emitting diodes(LEDs), are placed in an annular or ring shape around part of the endeffector and are configured to shine forward to illuminate the tool oraccessory held by the end effector and the workpiece being machined bythe tool. The end effector may be a tool or accessory holder mounted toan output spindle of the tool as described in U.S. patent applicationSer. no. 12/394426, entitled “Bit Retention Device” filed on Feb. 27,2009, the contents being incorporated herein by reference in itsentirety. Other examples of end effectors that may be used in accordancewith the invention may be the 7000 Series chuck manufactured andmarketed by the Jacobs Chuck Manufacturing Company of Clemson, S.C., andquick change chucks similar to that found on products such as a DC825KAImpact Driver and a DC815KA Impact Driver manufactured and marketed bythe DeWalt Industrial Tool Company of Baltimore, Md.

Several different types of lighting elements can be used in accordancewith the invention, such as light bulbs (for example, xenon bulbs) orother lighting elements. While having specific advantage, the LED lightsdiscussed herein are an example, and do not limit embodiments inaccordance with the invention to tools using LEDs. The LED lights, orother lighting elements, and associated parts are locked to the housingof the tool and do not rotate when the power tool is operated. It is,however, envisioned that the light elements can be incorporated into arotatable member such as a chuck tightening ring. The lights may bepowered by the same power source that provides power to the power tool'smotor. In the case of cordless power tools, a battery powers the powertool and in the case of corded tools AC current is provided from asource voltage through a cord. This AC current may be modified accordingto the needs of the lighting device being employed. In the case of LEDlights, a rectifier may be employed to convert AC current to DC.

A first embodiment in accordance with the present teachings isillustrated in FIG. 1 a. The power tool 50 has a housing 51 which can beof a clam shell type or any other suitable type housing. The power tool50 may have a transmission housing 56 located at the front portion ofthe power tool 50 to encapsulate a portion of an end effector 53. Ahandle 57 projects downwardly from the housing 51 and is terminated witha battery. The transmission housing of the embodiment of FIG. 1 acontains a speed reduction transmission (e.g., a single-stage planetarytransmission) and an impact mechanism that provides an intermittentrotary impact to the end effector (e.g., a Pott mechanism). Thetransmission housing of the embodiment of FIG. 1 b contains a speedreduction transmission (e.g., a multi-stage planetary transmission) andat least a portion of a torque clutch that disengages when apredetermined torque is reached.

The end effector 53 may be configured to hold an accessory or tool suchas a drill bit or a driving type accessory such as a Philips or standardscrewdriver. Other types of tools or accessories may be held and used inthe end effector 53 as can be appreciated by one skilled in the art. Themovement of the end effector 53 may be controlled by the trigger 55. Thetrigger 55 may selectively provide power from the battery to the motorlocated within the housing 51. In some embodiments of the invention, themore the trigger or switch 55 is depressed the more power may be appliedto the motor which may cause the end effector 53 to spin faster. Thebattery provides the power to energize the motor and controllably turnthe end effector 53.

As shown in FIG. 1 b and as described in U.S. patent application Ser.No. 12/379,585, entitled “Light for a Power Tool and Method ofIlluminating” filed on Feb. 25, 2009, the contents being incorporatedherein by reference in its entirety, the power tool 50 may be equippedwith a clutch collar. Although not shown, other embodiments inaccordance with the teachings may not have a rotating clutch collar, butrather a different mechanism, such as a drill/hammer mode selector, agear shifter, an on/off switch, a variable speed control, or othercontrol mechanism. However, this specification will refer to a clutchcollar as an example but does not limit embodiments in accordance withthe invention to tools having clutch collars. The clutch collar may berotated to adjust the torque setting at which the clutch disengages. Anumbered scale may appear on the clutch collar in order to provide auser an indication of the setting of the clutch collar. In someembodiments the user may turn the clutch collar to a desired position byhand An example of a clutch and transmission that may work in accordancewith the invention is shown in U.S. Pat. No. 7,066,691 which isincorporated by reference in its entirety. Of course, other types ofclutch and transmission mechanisms may be used in accordance with theinvention.

The power tool 50, for example, can be equipped with a light emittingholder 52 at an end of the transmission housing 56. As described below,the holder 52 functions to couple a lighting circuit to a tool housing51. A transparent or transparent cover 54 is shown mounted in a recessdefined in the holder 52. The holder 52 is mounted to the transmissionhousing 56 which is, in turn, supported by the housing 51. A chin shroud62 is located on the holder 52 and provides a housing for a portion ofthe wires 64 (See FIG. 2). The wires 64 have a connector 66 at a firstend 68 are coupled at a second end 70 to a circuit board 82 disposedwithin the holder 52.

FIG. 2 represents a perspective view of the holder 52 transmissionhousing 56 subassembly. Shown is the holder 52 having the associatedtransparent cover 54 fixably coupled to the housing transmission housing56. An associated pig tail wire assembly 71 with associated connector 66is positioned to allow the coupling to correspondingly connect on thehousing 51. The transmission housing 56 has an associated couplingmechanism 55 which is used to mate the transmission housing 56 to thetwo-piece housing 51.

FIG. 3 represents a cross-sectional view of the holder 52 transmissionhousing 56 subassembly. The holder 52 can be coupled to the transmissionhousing 56 using a plurality of snap features, or bayonet mechanisms 74which are configured to interface with a corresponding L-shaped channel76 defined within the transmission housing 56. Disposed within a channel78 defined by the holder 52 is the transparent cover 54. As describedbelow, the transparent cover 54 itself defines a transparent coverchannel 80 which annularly supports an associated circuit board 82having a plurality of surface mounted light emitting diodes (LEDS) 84.As described in detail below, the circuit board 82 is held into thetransparent channel 80 using a locking member 86 which is heat staked tothe circuit board 82 to effect a solid non-rotatable fixation of thecircuit board to the transmission housing 56.

The holder 52 is coupled to a stepped portion 88 of the transmissionhousing 56. The stepped portion 88 has a first surface 90 which isgenerally parallel to the centerline 92 of the tool 50. Generallyperpendicular to this surface is a second surface 94 which acts as anabutment for the holder 52. The first surface 90 of the stepped portion88 has a protruding flange 96 which functions as a locking feature tocouple the holder 52 into the stepped portion 88. The flange 96 has aramped surface 98 which facilitates the snapping of a correspondingholder 52 locking feature 100 onto the stepped portion 88. Definedwithin a second portion 102 the first surface 90 comprises the lockinggroove or channel 76. The locking groove 76 is annularly formed withinthe second portion 102 or can be formed of a plurality of radiallydisposed intermittent coupling grooves. The locking feature 74 comprisesa chamfered flange member 106 having a ramped interfaced surface 108 andopposed planar bearing surface 110. The planar bearing surface 110 isconfigured to interface with a corresponding planar bearing surface 111defined either on the flange 96 or locking groove or channel 76 definedwithin second portion 102 of the first surface 90.

FIG. 4 represents a perspective view of the holder 52 in subassemblyform. The holder 52 contains a mounting member 108 which defines aplurality of radially disposed coupling slots 110. The slots 110 areconfigured to accept a corresponding set of transparent cover snapcoupling members 112. The snap coupling members 112 are configured tobear against an inner surface 114 of the mounting member 108. Protrudingfrom the inner surface 114 are three depending coupling flanges whichare configured to couple the holder 52 to the transmission housing 56.

The holder 52 has a generally cylindrical exterior surface 118. Theexterior surface 118 functions to encapsulate the transparent cover 54,mounting member 108 and circuit board 82. The mounting member 108 has adepending wire support member 120 having a center flanged portion 122which defines a pair of generally elongated wire bearing slots 124. Theslots are configured to accept the pair of power wires 64 from the wireharness pig tail assembly 71. The wire support member 120 is generallydisposed within the chin shroud 62 and facilitates the protection of thelight source power wires. The mounting member 108 defines an axialthrough bore 126. The through bore 126 has an inner surface 128 with aplurality of associated stand off flanges 130. The stand off flanges 130function to apply pressure onto the circuit board 82 when the mountingmember is engaged with the holder 52. Further defined within the innersurface 128 is a notch 132 configured to accept a wire harness strainrelief member 134. The wire harness strain relief member 134 has a pairof curved internal surfaces which accept the bent wires 64 in a mannerto minimize the overall axial length of the holder 52.

FIG. 5 represents a rear perspective view of the transparent cover 54circuit board 82 subassembly. As shown, the circuit board 82 isgenerally circular and is disposed within the transparent cover channel80. The circuit board 82 defines a plurality of radially disposednotches 136 on the exterior radial periphery of the circuit board. Thenotches 136 accept corresponding flanges 86 which are defined radiallywithin an inner bearing surface 140 of the transparent cover channel 80.Defined within the transparent cover and adjacent to the flanges 138 arecorresponding notches 142 which have a depth generally corresponding tothe locational position of the circuit board 82. After the circuit board82 is placed within the channel 80, the flanges 138 are melted, therebyfixably coupling the circuit board 82 within the transparent cover 54using a heat staking process.

The couplers or attachment mechanisms between the circuit board 82 andthe transparent cover 54, the holder 52 and the transmission case 56, orthe holder 52 and the transparent cover 54 can take the form of the heatstake joint, the bayonet joint, or the locking flange within a slot,exemplary embodiments of which are described above. The couplers orattachment mechanisms are configured to withstand the extreme cyclictorsional loading associated with hand held power tools. In this regard,the joints are configured to prevent vibrational noise or damage tothese components, especially to the PCB.

FIGS. 6 and 7 represent cross-sectional perspective views of thesubassembly shown in FIG. 5. Shown is the transparent cover channel 80,a coupling flange 138, relief member 134 and snap member 112. Thechannel 80 defines an inner ledge 142 which axially supports the circuitboard 82 in a position which axially locates the LED 84 at the properdistance from the transparent cover 54. The distance allows for theproper focusing of the light from the LED on to a workpiece.

FIG. 8 represents a front view of the transparent cover/circuit boardsubassembly shown in FIGS. 5 and 6. Shown is the positional position ofthe LEDs 84 with respect to the various snap and coupling features.While surface mounted LEDs 84 are shown and have their own particularadvantages, it should be envisioned that non-surface mount LEDs could beused. Shown adjacent to the LEDs 84 is a plurality of surface mountedresistors 151 which are electrically coupled to the LEDs 84.

FIGS. 9-11 represent an alternate holder 52 having an alternate circuitboard to transparent cover coupling mechanism. In this regard, theholder 52 contains a transparent cover 150 having an inner tubularmember 152. The inner tubular member 152 defines a generally L-shapedcoupling channel 154. The L-shaped coupling channel 154 defines aprotruding locking feature 156 which engages a corresponding lockingbayonet feature on the transmission housing.

Further defined on the inner tubular member 152 is a plurality ofcoupling notches 158. The notches 158 have a depth corresponding to thepreferred locational position of the circuit board 82 within thetransparent cover channel 80. Adjacent to the coupling notches 158 arecorresponding coupling flanges 160 which are configured to be positionedwithin a corresponding set of notches 162 defined within an innersurface 164 of the circuit board 72. As described above, the couplingflanges 160 are configured to be melted in a heat staking process torotationally and longitudinally fix the circuit board 82 within thechannel 80. As best seen in FIG. 11, the holder can define discreteapertures to allow light to be emitted from the nose section of the toolonto the workpiece. The holder 52 has a elastomeric overmolding toprevent damage to the workpiece and to the tool if the toolinadvertently strikes the workpiece.

The foregoing description of the embodiments has been provided forpurposes of illustration and description. It is not intended to beexhaustive or to limit the disclosure. Individual elements or featuresof a particular embodiment are generally not limited to that particularembodiment, but, where applicable, are interchangeable and can be usedin a selected embodiment, even if not specifically shown or described.The same may also be varied in many ways. Such variations are not to beregarded as a departure from the disclosure, and all such modificationsare intended to be included within the scope of the disclosure.

Example embodiments are provided so that this disclosure will bethorough, and will fully convey the scope to those who are skilled inthe art. Numerous specific details are set forth such as examples ofspecific components, devices, and methods, to provide a thoroughunderstanding of embodiments of the present disclosure. It will beapparent to those skilled in the art that specific details need not beemployed, that example embodiments may be embodied in many differentforms and that neither should be construed to limit the scope of thedisclosure. In some example embodiments, well-known processes,well-known device structures, and well-known technologies are notdescribed in detail.

The terminology used herein is for the purpose of describing particularexample embodiments only and is not intended to be limiting. As usedherein, the singular forms “a,” “an,” and “the” may be intended toinclude the plural forms as well, unless the context clearly indicatesotherwise. The terms “comprises,” “comprising,” “including,” and“having,” are inclusive and therefore specify the presence of statedfeatures, integers, steps, operations, elements, and/or components, butdo not preclude the presence or addition of one or more other features,integers, steps, operations, elements, components, and/or groupsthereof. The method steps, processes, and operations described hereinare not to be construed as necessarily requiring their performance inthe particular order discussed or illustrated, unless specificallyidentified as an order of performance. It is also to be understood thatadditional or alternative steps may be employed.

When an element or layer is referred to as being “on,” “engaged to,”“connected to,” or “coupled to” another element or layer, it may bedirectly on, engaged, connected or coupled to the other element orlayer, or intervening elements or layers may be present. In contrast,when an element is referred to as being “directly on,” “directly engagedto,” “directly connected to,” or “directly coupled to” another elementor layer, there may be no intervening elements or layers present. Otherwords used to describe the relationship between elements should beinterpreted in a like fashion (e.g., “between” versus “directlybetween,” “adjacent” versus “directly adjacent,” etc.). As used herein,the term “and/or” includes any and all combinations of one or more ofthe associated listed items.

Although the terms first, second, third, etc. may be used herein todescribe various elements, components, regions, layers and/or sections,these elements, components, regions, layers and/or sections should notbe limited by these terms. These terms may be only used to distinguishone element, component, region, layer or section from another region,layer or section. Terms such as “first,” “second,” and other numericalterms when used herein do not imply a sequence or order unless clearlyindicated by the context. Thus, a first element, component, region,layer or section discussed below could be termed a second element,component, region, layer or section without departing from the teachingsof the example embodiments.

Spatially relative terms, such as “inner,” “outer,” “beneath,” “below,”“lower,” “above,” “upper,” and the like, may be used herein for ease ofdescription to describe one element or feature's relationship to anotherelement(s) or feature(s) as illustrated in the figures. Spatiallyrelative terms may be intended to encompass different orientations ofthe device in use or operation in addition to the orientation depictedin the figures. For example, if the device in the figures is turnedover, elements described as “below” or “beneath” other elements orfeatures would then be oriented “above” the other elements or features.Thus, the example term “below” can encompass both an orientation ofabove and below. The device may be otherwise oriented (rotated 90degrees or at other orientations) and the spatially relative descriptorsused herein interpreted accordingly.

What is claimed is:
 1. A power tool comprising: a housing; an endeffector rotatable with respect to the housing; an annular collardefining a channel therein, said collar being coupled to the housing; anannular printed circuit board disposed within the channel; an annulartransparent cover disposed within the annular collar, said transparentcover being rotatably and axially fixed to the printed circuit board;and a plurality of lighting elements operatively connected to theprinted circuit board and radially disposed about the end effector toilluminate a workpiece.
 2. The power tool of claim 1, wherein thelighting elements are a plurality of light emitting diodes radiallydisposed about the printed circuit board, and wherein a portion of theend effector extends through a hole defined by the transparent cover andprinted circuit board.
 3. The power tool of claim 1, wherein thetransparent cover defines a groove and the printed circuit board isrotationally fixed within the groove.
 4. The power tool of claim 3,further comprising a plurality of heat meltable features on thetransparent cover configured to allow the printed circuit board to befixed into the groove in the transparent cover.
 5. The power tool ofclaim 1, further including a chin portion defined by the annular collar,the chin portion providing a protective case for wires operable coupledto the lighting elements.
 6. The power tool of claim 5, furthercomprising a plug terminating the wires and wire holding structure onthe chin portion for securing the wires in place.
 7. The power tool ofclaim 1, further comprising collar fasteners defined on the annularcollar configured to couple the annular collar to the housing.
 8. Thepower tool of claim 1, further comprising alignment grooves on theprinted circuit board and alignment tabs on the transparent cover, thealignment grooves on the printed circuit board and the alignment tabs onthe transparent cover are dimensioned and located so that the alignmentgrooves on the printed circuit board rotatably fit into and are retainedon the alignment tabs on the transparent cover to keep the printedcircuit board and the transparent cover aligned.
 9. The power tool ofclaim 1, further comprising engaging structure on the transparent coverconfigured to bear against corresponding engaging structure on atransmission housing to lock the transparent cover from rotating withrespect to the transmission housing.
 10. The power tool of claim 1,further comprising a coupling member covering the printed circuit boardso that the lighting element and the printed circuit board aresubstantially entrapped by the coupling member and the transparentcover.
 11. The power tool of claim 9, wherein the coupling member isaxially retained by the annular holder and attached to a transmissionhousing.
 12. The power tool of claim 11, further comprising a steppedportion on the transmission housing wherein the annular holder residesin the stepped portion.
 13. The power tool of claim 14, wherein theannular collar is axially locked to the transmission housing at least inpart by the annular holder.
 14. A power tool comprising: a rotatable endeffector; an annular collar; an annular printed circuit board; lightelements operatively connected to the annular printed circuit board andbeing adjacent to the end effector to illuminate a workpiece machined bythe power tool; and an annular cover having a transparent region, saidannular cover axially supporting the printed circuit board, wherein aportion of the end effector extends through a hole defined by the coverand printed circuit board and wherein the cover defines a groove and theprinted circuit board is located in the groove.
 15. The power tool ofclaim 14, further comprising a heat meltable flange on the transparentcover configured to allow the printed circuit board to be non-rotatablyfixed into the groove in the transparent cover and held in place in thetransparent cover.
 16. A power tool comprising: a motor housing; ahandle coupled to the motor housing; a transmission case coupled to themotor housing; an end effector extending from the transmission case; asubstantially annular collar; a substantially annular circuit boardhaving a plurality of light emitting elements; a substantially annularcover defining a channel and having a transparent portion; a firstcoupler disposed between the collar and the transmission case, saidfirst coupler preventing axial displacement of the collar with respectto the transmission case; a second coupler disposed between the circuitboard and the cover, said second coupler preventing axial and rotationaldisplacement of the circuit board with respect to the cover; a thirdcoupler disposed between the collar and the cover, said third couplerpreventing axial displacement of the cover with respect to the collar;and wherein at least a portion of the end effector extends through thecollar, the circuit board, and the cover.
 17. The power tool accordingto claim 16, wherein at least one of the first coupler, the secondcoupler, and the third coupler comprises at least one of a heat stakejoint, a bayonet joint, and an engaged flange.
 18. The power toolaccording to claim 16, wherein the cover defines an annular groove andthe circuit board is disposed therein.
 19. The power tool according toclaim 16, wherein at least a portion of the cover is disposed throughthe collar portion.
 20. The power tool according to claim 16, whereinthe cover is transparent.